Continuous vacuum drying apparatus for cloth and associated method



1957 MITSUYUKI SUZUKI ETAL 3,355,813

CONTINUOUS VACUUM DRYING APPARATUS FOR CLOTH AND ASSOCIATED METHOD Filed Nov. 16, 1966 3 Sheets-Sheet 1 1967 MITSUYUKI SUZUKI ETAL 3,355,313

CONTINUOUS VACUUM DRYING APPARATUS FOR CLOTH AND ASSOCIATED METHOD Filed Nov. 16, 1966 5 Sheets-Sheet 2 1967 MITSUYUK! SUZUKI ETAL 3,3

CONTINUOUS VACUUM DRYING APPARATUS FOR CLOTH AND ASSOCIATED METHOD Filed Nov. 16, 1966 5 Sheets-Sheet 5 United States Patent 3,355,813 CONTINUOUS VACUUM DRYING APPARATUS FOR CLOTH AND ASSOCIATED METHOD Mitsuyuki Suzuki and Eiichi Yoshida, Ashikaga-shi, Ja-

pan, assignors to Kabushiki Kaisha Kobayashi Kikai Seisakusho, Tochigi-ken, Japan Filed Nov. 16, 1966, Ser. No. 594,854 Claims priority, application Japan, Nov. 16, 1965,

til/69,959, 40/653,960 11 Claims. (CI. 34-16) This invention is directed to methods and apparatus for drying cloth. In conventional methods for drying cloth such as woven cloth or knitted cloth or the like, the cloth is brought into contact with a heating member such as a cylinder dryer or with hot air. These conventional methods in which high temperature is used, often produce deterioration of the cloth such as by causing surface hardening or the like and are not suitable when bulkiness of cloth after finishing is required. To avoid this disadvantage, it is desirable to effect drying at the lowest possible temperature.

For this reason, the present invention is directed to a drying apparatus in which drying is effected at an extremely low temperature by heating the cloth under vacuum or nearly vacuum conditions in a drying chamber. A continuous operation is carried out by maintaining the inlet and outlet in the chamber for the passage of the cloth hermetically sealed.

According to the present invention; 'a casing having a drying chamber with a number of rotary heating drums is provided, at the inlet and outlet openings of the chamber, with cloth handling apparatus, such apparatus comprising a pair of spaced rotatable rollers each being in hermetically sealed contact at its periphery and both end surfaces with the casing, an idle roller having an elastic surface in hermetically sealed contact at both its ends with the casing and extending between and in close contact at its elastic surface with the peripheral surfaces of said pair of rotating rollers, and a pressure roller applied to the external surface of said idle roller. Thus, each handling apparatus hermetically seals the drying chamber of the casing against the external atmosphere but allows the cloth to pass through said chamber.

An embodiment of the present invention will now be described with reference to the accompanying drawing, wherein:

FIGURE 1 is a front view of the apparatus according to the present invention;

FIGURE 2 is a side view of the same;

FIGURE 3 is a sectional view taken along the line IIl-III in FIG. 1;

FIGURE 4 is an enlarged sectional view of a portion thereof;

FIGURE 5 is a sectional view taken along the line VV in FIG. 4; and

FIGURE 6 is a sectional view taken along the line VI-VI in FIG. 4.

Numeral 1 denotes a machine frame, and numeral 2 denoted a casing carried thereby. Within a drying chamber of the casing 2 there are mounted a pair of cylindrical rotary heating drums 3 which are driven in rotation in reverse directions, as shown by the arrows in FIG. 2, by an electric motor 4 and a gear mechanism 5 located at the outside of the machine frame 1. The drums 3 are heated by introducing steam therein. The interior of the drying chamber of the casing 2 is in communication with a condenser '7 and the suction side of a blower 8 through a conduit pipe 6 for maintaining a vacuum condition within the interior of the drying chamber.

The casing 2 is provided at its upper and lower sur faces with inlet and outlet openings 9 and there are pro- 3,355,813 Patented Dec. 5, 1967 vided adjacent each of these openings, cloth handling apparatus A, one for feeding the cloth a to be dried into the casing 2 and the other for removal of the dried cloth from the casing 2. Adjacent each opening 9 is an outwardly projecting tubular casing 10 of rectangular outline with opposite side walls 11 extending parallel with the axis of the rotary heating drums 3 and nearly semi-circular in cross-section as shown in FIG. 3. A pair of rotatable rollers 12 are disposed in casing 10 parallel with one another and are driven in rotation in the same direction as shown by the arrows in FIGS. 3 and 4 by gears 15 through a rotary shaft 14 driven by an external electric motor 13.

A member 16 having an inwardly directed groove 17 is provided along the outer edge of each side wall 11, and a slidable member 18 made of an elastic material such as rubber, in H-shape in section, is slidably contained therein so that by applying high pressure air to the inside surface of member 18 within the groove 17, an elastic member 19 attached to the outside of member 18 is brought into contact under pressure with the peripheral surface of corresponding rotating roller 12 throughout almost the entire length thereof to establish a hermetic seal thereat. As shown in FIG. 5 each end surface of each rotating roller 12, forms a surround annular space 20 with the inner surface of the tubular casing 10. An elastic strip 21 is interposed in space 20 and is bent into nearly V-shrlpe in section, whereby the interior oflthe casing 10 is sealed hermetically against the ambient atmosphere at each end surface portion of the rotating roller 12.

An idle roller 22 is disposed between each pair of rorating rollers 12 and contacts the external surfaces of the pair of rotating rollers 12 to be driven in the direction shown by the arrows in FIGS. 3 and 4. Each roller 22 is devoid of a shaft and comprises a metal cylindrical drum 23 covered by an elastic covering tube 24 made of an elastic material such as rubber, which is in contact at covering tube 24 with the rotating rollers 12. The roller 22 is supported at both end surfaces thereof by receiving plates 26 which are integral with the machine frame 1.

Each receiving plate 26 has a circular recess in which an elastic ring 28 of U-shape in section is disposed with its external surface in contact along the inner circumferential surface of the recess 27. An elastic disc 29 is located in the recess 27 with one side in contact with the ring 28 and its opposite side in contact with end surface 25 of the roller 22, so that by applying high pressure air into the interior of the recess 27 the ring 28, disc 29 and end surface 25 are brought into contact under pressure one with another to provide a hermetic seal therebetween.

A pressure roller 30' extends longitudinally with the idie roller 22 at the outside thereof. The pressure roller 31) is supported by a shaft 31 from the machine frame 1 for adjustment by an adjusting mechanism 32 to regulate the contact pressure of the idle roller 22 against the rototing roller 12.

The adjusting mechanism 32 comprises a diaphragm 34 provided within a casing, and a rod 35 supporting the shaft 31 and connected to the diaphragm 34, so that by applying air at regulated pressure to one side of the diaphragm 34, the idle roller 22 can be pressed via the pressure roller 30 with adjustable pressure against the rotating rollers 12.

Numeral 36 denotes a steam conduit for supplying steam to the rotary heating drum 3, and numeral 37 denotes compressed air supply conduits in communication with each groove 17, each recess 27 and the rear surface of the diaphragm 34, respectively.

. When in operation, the interior of the casing 2 is maintained hermetically sealed against the ambient atmosphere and is subjected to a vacuum while the heating drums 3 are supplied with steam for being kept at a temperature effective to dry the cloth. The cloth is fed between the idle roller 22 and the rotating rollers 12 of the feed apparatus A at the bottom of the casing 2 and is advanced through guide rollers 38 for being brought into contact in succession at its front and rear surfaces alternatively with the pair of rotary heating drums 3 to be heated and dried during such travel at a relatively low temperature. Then the dried cloth is led out of the casing 2 between the idle roller 22 and the rotating rollers 12 of the handling apparatus A at the top of casing 2 for removal therefrom, said cloth being guided through a guide roller 39 to a plaiting device 40.

According to the present invention, as described above, the interior of the casing is sealed hermetically at its cloth inlet and outlet portions against the ambient atmosphere, so that the interior of the casing can be kept effectively in a vacuum condition, whereby the cloth may be dried therein at a low temperature to obtain products of good quality. Additionally, each cloth handling apparatus respectively serves to lead the cloth into and out of the casing continuously, so that a continuous drying operation may be obtained. Additionally, since the idle roller is not driven externally, hermetic sealing at its both end surfaces may be easily obtained, and the pressure force thereof against the rotating rollers can be adjusted easily and accurately by the pressure roller applied at the external surface thereof so that hermetic sealing at the contact surfaces may be effectively obtained.

There will now become apparent to those skilled in the art, numerous variations and modifications of the disclosed embodiment without departing from the scope and spirit of the invention if defined by the attached claims.

What is claimed is:

1. A continuous operation vacuum drying apparatus for cloth comprising a casing having a drying chamber which is adapted for being subjected to a vacuum, said casing having an inlet and an outlet for the passage of cloth through said chamber, a plurality of rotary heating drums in said chamber for heating the cloth during its passage therethrough to dry the cloth, handling means for said cloth at said inlet and outlet for respectively feeding the cloth into and removing the cloth from the chamber while maintaining a hermetic seal at said inlet and outlet, each handling means comprising a pair of spaced rotatable rollers, each roller having end surfaces and a peripheral surface in hermetically sealed contact with the casing, an idle roller having end surfaces in hermetically sealed contact with the casing, said idle roller having an elastic peripheral surface and extending between and in close contact at said elastic peripheral surface with the peripheral surfaces of said pair of rotatable rollers, and a pressure roller applied to the peripheral surface of said idle roller to urge the idle roller against the rotatable rollers.

2. Apparatus as claimed in claim 1 comprising \means for driving the rotatable rollers of each pair in the same direction to produce rotation of the idle rollers.

3. Apparatus as claimed in claim 2 wherein the idle rollers have fiat end surfaces which are devoid of shafts.

4, Apparatus as claimed in claim 1 wherein each said handling means comprises a slidable member supported from the casing adjacent the periphery of each rotatable roller, an elastic member carried by said slidable member and facing the periphery of the rotatable roller, and means for applying the force of a pressure fluid against the slidable member to urge the elastic member into sealing contact with the rotatable roller.

5. Apparatus as claimed in claim 4 wherein each said idle roller comprises a cylindrical drum having opposite ends, and an elastic covering on said drum forming said elastic peripheral surface of the idle roller, said elastic covering projecting axially beyond the ends of the cylindrical drum and providing said end surface for the idle roller.

6. Apparatus as claimed in claim 5 wherein said casing is provided with a recess adjacent the end surfaces of each idle roller, each handling means comprising means for sealing the end surfaces of the associated idle roller including a resilient disc in each recess and means for applying the force of a pressure fluid against the discs to urge the same into sealing contact with the elastic covering at the edges thereof which define said end surfaces of the idle roller.

7. Apparatus as claimed in claim 6 comprising means engaging each pressure roller to urge the same with a regulable force against the associated idle roller.

8. Apparatus as claimed in claim 7 wherein each said pressure roller has a shaft, said means which urges each pressure roller against the associated idle roller comprising a displaceable rod supporting the shaft of such pressure roller, a diaphragm connected to each rod and defining closed chambers on opposite sides of the diaphragm and means for applying a regulable force of a pressure fluid against the diaphragm to urge the pressure roller against the idle roller in an adjustable degree.

9. Apparatus as claimed in claim 8 comprising compressed air supply conduits in communication with said slidable members, said recesses and said diaphragms.

10. Apparatus as claimed in claim 1 comprising guide rollers in said chamber for directing the cloth to pass alternately with one surface thereof over one drum and with its other surface over the other drum.

11. A method of drying cloth with the apparatus as claimed in claim 1 comprising continuously feeding cloth through a drying chamber by continuously passing the cloth into the chamber at an inlet thereof and continuously drawing it from an outlet thereof, maintaining a suction pressure within the chamber, heating the cloth at relatively low temperature sufiicient to dry the same as the cloth passes through the chamber, and hermetically sealing the inlet and outlet of the chamber while continuously advancing the cloth therethrough.

References Cited UNITED STATES PATENTS 612,931 10/1898 Parker et al. 34-92 1,565,494 12/1925 Patterson 34-92 1,595,240 8/1926 Minton 34-16 2,518,268 8/1950 Bancroft 34--16 2,963,001 12/1960 Alexander 3416 3,071,866 1/1963 Mangus 3492 WILLIAM J. WYE, Primary Examiner. 

1. A CONTINUOUS OPERATION VACUUM DRYING APPARATUS FOR CLOTH COMPRISING A CASING HAVING A DRYING CHAMBER WHICH IS ADAPTED FOR BEING SUBJECTED TO A VACUUM, SAID CASING HAVING AN INLET AND AN OUTLET FOR THE PASSAGE OF CLOTH THROUGH SAID CHAMBER, A PLURALITY OF ROTARY HEATING DRUMS IN SAID CHAMBER FOR HEATING THE CLOTH DURING ITS PASSAGE THERETHROUGH TO DRY THE CLOTH, HANDLING MEANS FOR SAID CLOTH AT SAID INLET AND OUTLET FOR RESPECTIVELY FEEDING THE CLOTH INTO AND REMOVING THE CLOTH FROM THE CHAMBER WHILE MAINTAINING A HERMETIC SEAL AT SAID INLET AND OUTLET, EACH HANDLING MEANS COMPRISING A PAIR OF SPACED ROTATABLE ROLLERS, EACH ROLLER HAVING END SURFACES AND A PERIPHERAL SURFACE IN HERMETICALLY SEALED CONTACT WITH THE CASING, AN IDLE ROLLER HAVING END SURFACES IN HERMETICALLY SEALED CONTACT WITH THE CASING, SAID IDLE ROLLER HAVING AN ELASTIC PERIPHERAL SURFACE AND EXTENDING BETWEEN AND IN CLOSE CONTACT AT SAID ELASTIC PERIPHERAL SURFACE WITH THE PERIPHERAL SURFACES OF SAID PAIR OF ROTATABLE ROLLERS, AND A PRESSURE ROLLER APPLIED TO THE PERIPHERAL SURFACE OF SAID IDLE ROLLER TO URGE THE IDLE ROLLER AGAINST THE ROTATABLE ROLLERS.
 11. A METHOD OF DRYING CLOTH WITH THE APPARATUS AS CLAIMED IN CLAIM 1 COMPRISING CONTINUOUSLY FEEDING CLOTH THROUGH A DRYING CHAMBER BY CONTINUOUSLY PASSING THE CLOTH INTO THE CHAMBER AT AN INLET THEREOF AND CONTINUOUSLY DRAWING IT FROM AN OUTLET THEREOF, MAINTAINING A SUCTION PRESSURE WITHIN THE CHAMBER, HEATING THE CLOTH AT RELATIVELY LOW TEMPERATURE SUFFICIENT TO DRY THE SAME AS THE CLOTH PASSES THROUGH THE CHAMBER, AND HERMITICALLY SEALING THE INLET AND OUTLET OF THE CHAMBER WHILE CONTINUOUSLY ADVANCING THE CLOTH THERETHROUGH. 